Means for heating boilers by waste gases.



, L. s. SCHMIDT.

A MEANS FOR HEATING BOILERS BY WASTE GA SES- APPLICATiO'N min FEB. 4, 1916.

Patented Aug. 20, 1918.

2 SHEETS-SHEET 1- III!! FIG.2.

WITNESSES INVENTOR L. S. SCHMIDT.

MEANS FOR HEATlNG BOILERS BY WASTE GASES. APPLICATION FILED m. 4, 1916.

2 SHEETS-SHEET 2.

Fll3.&.

WITNESSES Patented Au 20, 1918.

forHeatin iwhi'ch the f My invention relates I .heating waste heat 1 heretofore been 0. valve leakage is.

relates and to mwnmrca s. scmumr, or rrr'rsnunen, ramsnvem' I means r012. nmrme' 3mm BY was'rr. eases.

' it may concern.

Be 'it known that I, Lawmnwr; S. Sonmnr,

a citizen of the United States, residing at Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Means Boilers by Waste Gases, of lowing is a specification.

boilers by the waste gases of open hearth and other regenerative furnaces, being particularly designed to provide for maximum eificienc'y of said gases when utilized for boilers. he utilization of the waste heat from re- I generative furnaces practised but the means em-' ployed have been of such a character that they have not proven satisfactory due to heat losses and operating conditions present in the structures employed.

Heretofore, the waste gases have been passed to the waste heat boiler by means of a flue or passage directly connected with the passages being'employed to control the passa e of the waste gases, permitting the gasv to% e passed'to'. the boiler or to the stack, as desired.

Waste gases. from the open hearth and the checker" c ambers carry considerable dust and where these gases are employed for heat- I T ing boilers, the dust is dep'osited on the boilers, thus. requiring frequent cleaning. With the present structures this cleaning has been performed under greatdifliculties, due primarily m thsleakage of'gas past the valve in the flue or .1: Waste ses on their way to the boiler to be heated.

- To overcome the above stated troubles now represent in structures to which this invention pass the gases from the regenerative furnate to the boiler with a minimum heat loss'are'among theob ects of the present invention. v

In ac0omplishingtheseobjects, I employ j Specification of Letters Iatent. e se... filed February 4, 1910. Serial no;

to means for heating for heating boilers has stack or with-fthe stack flue,"v alves in-said passage leading to the boiler. Another objectionable feature also due: to

the admission of air to the Patented Aug. 20, 1918.

rearrangement the furnace, provided, eliminating the heretofore employed and a construction in which a of the connections between boiler and stack is direct connections employing a new and improved valve structure and port sealing-means-' of a character that will not lower the'temperature of the gasesin passing to the boiler.

In the accompanying drawin in which parts in each of the views,

similar reference characters indicate similar' Figure 1 is a diagrammatic view showing 'j. one way in which the conduits maybe ar ed toefiiciently carry out thepurposes ran oft 'e present invention.

Fig. 2 is a side elevation of a preferred form of valve, the view showing more particularly the mechanism for providing the I I shifting operations. 3 is a vertical the line 3 3 of Fig. 5, the view also showing portions of the conduits. I

Figs.- 4- and 5 are sectional views takenon the lines H and 5-5 respectively of Fig. 3. Referring moreparticularl'y to Fig. 1, 10 and 10* indicate air ports of the regenerative or open hearth furnace structure ;'11 and 11 represent the gas intake ports,and 12'and 12 the gas ports. 13 indicates a conduit or flue which, under prior practice, generally leads direct to the stack, indicated at 14.

his flue isbrought into orts 10 or 10" and ports 12 or 12* e use of a suitable valve mechawith the through t 'nism whic scribed, although ployed. Instead, however, flue 13 directto the stack, flue 13 terminates in a vertically extending port 13* arranged between two vertically extending ports 14 and 13, portlel being one entrance to a conduit 14 leading to ment being such that when port 13 is con nected to port 14 the gases from' the furnace, after reaching conduit 13 from the respective conduits, will pass direct to the stack. If, however, portl3is connected to port 15*, these gases will pass from conduit proper connection 7 may be of the type presently deother forms may be em-- of leading the transfer sectional view taken on the. stack, the arrange- 13 into conduit 15 leading to the boiler 16, i

the latter having an ofi-take 17 which leads to the stack. I prefer to employ an exhauster 18 at the outlet, side of the boiler in order that the draft an "merited.

his arrangement necessitates connection of port 13 with either of ports 14* or 15, depending upon whether the outgoing gases from the furnace are to be utilized in heating the boiler. By providing the break in continuity of the conduits, leakage of gases in the undesired path is prevented, so that when it is desired to clean the boilerfbrealting of the connections 15 prevents any liability of the gases entering the boiler while the workmen are present therein, the gases then being delivered to the stack, the boiler being by-passed. The stack, during this operation, is entirely disconnected from the boiler passage, and no air therefrom is drawn into the waste gases. To permit of placing the boiler into or out of the path of the gases at will, I employ a reversing valve structure, and to reduce heat losses at this point as far as possible, I preferably provide a reversing valve of the type indicated in the drawings, this arrangement operating to seal the connections, and at the same time materially reduce, if not entirely eliminate, the presence of an exposed water surface in the travel path of the gases.

As shown more particularly in Figs. 3 and 5, ports 13, 14 and 15 are formed with annular portions projecting above the normal plane of these conduits, these ports being preferably circular in contour, although this is not absolutely essential, it being clear that this contour may be varied in any desired manner.

Surrounding each of these annular portions of the port is a trough 19 adapted to carry the water for the water seal, these troughs being scomparatively narrow in cross sectional width and having sufficient depth to provide for proper sealing action. Cooperating with these ports is a reversing valve 20. This valve has a cross sectional contour corresponding to the contour of troughs 19, the drawing showing this cross sectional contour as circular. The travel path of the gases through the valve is also shown as being on. the arc of a circle, thereby eliminating as far as possible the direct impinging action of thegases which occurs where the valves are shallow.

In the drawing, the valve is shown tubular and preferably formed metallic with a lining 20*- of refractory material, the ends of the metallic portion projecting beyond the ends of the lining, these projecting portions 21 forming the parts which enter the troughs 19 to complete the seal. As shown,

1 also preferably provide an angle 22 at the of the stack may be between ports 13 and endsof the lining, nected to the metallic tube in suitable manner, serving not only to protect and position the ends of the lining but also; forming members which may contact with the inner seal of the trough and coact with the trough to support the valve, but in addition, act to segregate the seal from the gases, thus placing the seal entirely out of direct contact with the gases.

As will be obvious, the use of narrow troughs and the projecting portions 21 necessitates practicall a uniform vertical travel of the valve before its lateral shift ing movement can take place, since the projecting portions 21 must be entirely above the plane of the troughs before the lateral motion takes place. To provide for this action, I employ certain operating mechanisms which first act to raise the valve bodily, then s ift it in the proper direction without -naterially increasing the vertical travel after the seal has been broken,

and then permitting the valve to move downwardly to its new position by the action of gravity without, however, any material jar effect, these mechanisms automatically providing this shiftingaction and at the same time acting as locking means against accidental shifting of the valve when in either of its posltions. To provide this action, I employ the following mechanisms:

23 indicates a cam structure in the form of a plate member, one of these members being located on each of the opposite sides of the valve. As shown in Figs. 2 and 3, each member 23 is depressed substantially midway of its length as at 23*, the member on opposite sides of this depression forming cams 24 which have the cam faces similar in both cams. The vertical walls of depression 23 are shown as inclined from the vertical to a small degree, increasing the distance between the walls at the top of the depression, so that a member traveling over the face provided by either of these walls will tend to shift the valve slightly in the direction in which it is to move, this action continuing until the top face of the same is reached, said top face then permitting the valve to travel in the direction it is to go though the cam action shifts such plane.

these angles being conea Consequently, the projecting portions are maintained in proper position to enter the seals provided by the troughs whenever shifting of the valve carries it to a position where the vertical walls of the cams permit the valve to seat, the rollers 25 passing downward during this action.

26 and 26 indicate a pair of shafts which extend from one side of the valve to the other, each shaft being adapted to carry a pair of arms 27 having'slot 27, these slots being adapted to receive rollers 28 mounted on their axes, the

on shaft 29, said latter shaft also carrying rollers'25. Shafts 26 and 26 areprovided with aworm gear 30, each gear being adapted to cooperate with a worm 31 carried by a shaft 32, the latter being driven from a suitable power source, such,'for instance, as a motor, the power means being so arranged as to permit shaft 32 to be rotated in either direction. Obviously, rotation of shaft 32 will act to move shafts 26 and 26- movements of the shaft carrying arms 27, and since shafts 29 extend into the slots 27, such movements of arms 27 will provide movements to shaft 29 in the corresponding direction, but sinceshaft 29 is located within an elongated slot, movements of shaft 29 will not be on an arc having shafts 26 or 26 as a center, .but will, on the contrary, travel in paths which are controlled by cams 24, shaft 29 simply moving within the slot 27* as may be necessary in following the cam.

As will be readily understood from Figs. 2 and 3, in which the valve is shown as connecting ports 13 and 15, operation of shaft 32 in a direction to move arms 27 counterclockwise would first cause rollers 25 to travel up the vertical faces at the right of each cam 24.- until these rollers reached the point of juncture of the vertical and. horizontal faces of the cam, whereupon, the upper faces of the cams will form the support for the valve, arms 27 simply causing the valve to travel on its support, thus relieving these arms of the support of the valve which was placed on them during the initial vertical travel. The counter-clockwise travel of arms 27 causes the valve to travel toward the left of these figures, until rollers 25 reach the opposite end of the upper portion of cams 24, whereupon, the arms 27 again take up the support of the valve, continuation of these arms gradually lowering the valve into position, it being readily un dcrstood that when this lowering action is to take place, the arms are at such an angle to the vertical that free downward movement of the valve is prevented, the downward travel being dependent upon the speed at which the arms 27 travel. Consequently, the valve seats with a gentle motion and since one of rollers 25 passes into depression 23 whenever final downward movement of the valve takes place, the valve will be held from any material uncontrolled shifting by reason of the limited amount of play provided by the vertical walls ;of depression 23. Consequently, there is no necessity for the employment of troughs of considerable width, the walls of the depression 23 acting to prevent shifting of the valve sufficient to prevent entrance of pro jections 21 into the relatively narrow seal.

Since the initial and final travel of the valve is substantially vertical, thereby causing the projections 21 to leave or enter the seals without material lateral motion therein, it will be readily understood that movements of the considerable rapidit ,such initial and final movements being such as to not tend to materially disturb the water of the seal even when the withdrawing or entering movement is rapid. As lateral movement of the valve only takes place after the projections leave the seal, rapid travel in the lateral direction has no effect upon the seal. Consequently, the power device can operate with rapidity and at uniform speed, there being no requirement of any change speed action during the shifting operation.

As will be obvious, the worm and worm gear connection acts as a lock to prevent shifting of the arms 27 except when shaft 32 is operated, so thatthe position of the valve will be maintained. 7

It is to be understood that the operating structure, with the exception of the worm and gear connections and shaft 32, are duplicated on the opposite side of the valve.

ile the top cam surfaces of cams 24 might be in a single plane, I prefer to make these surfaces in two or more planes, the drawings showing two inclined to-the horizontal with the high portion substantially midway of the length of the cam, thus tending to gradually raise the valve during its lateral travel and insure free movement without, however, carrying the valve to any great extent above the top plane of the ports. As will ,be readily under'stood, the downward inclination of the cam during the latter half of its movement assisted by the weight of the valve, thus insuring against liability of any sticklng action between the arms and the valve;

it will be readily understood that the weight can not so affect the movement as to'cause planes, each slightly valve can be had with v travel of the valve in a manner to damage the structure.

Since the valve acts in connection with but two of the three ports when in its lower normal position, I provide means for 010s ing the remaining port at this time, this 34* which may located in the path valve,

means being in the form of a hingedly supported cover 33 carried'at each end of the the latter having a supporting ture indicated at 34, to which a member 35 secured to the top cover 33 having a downwardly extending flange, said flange conforming to the contour of the trough and being adapted to provide the sealed condition of the port when the latthe valve. As will be valve acts to raise the cover out of its sealed placing the cover ported at a suitable point, as at Condition, thereby permitting the valve to continue its movements without liability of the cover preventing such movement.

As there are but three ports to be controlled at this particular point, and two of these ports are controlled by. the valve, it

will be readily. understood that one of the covers 33 need perform no duty, and can therefore be raised. Various means, for

in raised position or roviding its movements may be employs a simple structure in which a cable 36 has its upper end sup- 37, and its lower end secured to the cover, each cover having its independent cable. As shown in Fig. 3, thecover at the left is in its portclosing position; however, the cover at the right is shown as raised, this being due to the fact that the point 37 is so positioned relative to the normal positions of the valves, that the length of cable between such point I and the cover will not permit the cover to follow the entire movements of the valve when shifting from one without the cover being moved on its pivot.

It should be understood that nism may also be employed in connection with the other ports re erred to, the employment of the valve disclosed herein decreasing the loss of heat units which occurs in connection with the other types. However, the application is not limited to a valve such as disclosed herein at these other ports, since it may be desired to reduce the temperature of the outgoing gas during a passage to conduit 13. It is, however, preferred to employ the type of valve disclosed herein as the connector between conduits 13 and 15 in order that a minimum reduction might be had at this point.

What I claim is:

1. In apparatus for utilizing waste gases in the heating of boilers and in combination, a boiler, a stack, a waste gas conduit having struc-- of cover"33f.is pivoted,

"nection with. one of a suitable stop 'tion, a boiler,

having a port, a

vertical .movements of the therebetween,

being indicated in Fig. 3

position tofthe otherthis mechaiaaaeat a port, a stack flue having a port, a boiler flue-having a port, all of sand ports arranged in-the same horizontal plane and having their axes approximately parallel, and ,a re-- versing valve mounted above said ports for connecting the waste gas. conduit with the boiler flue port or the stack flue port at will, the movement of said valve to establish consaid ports acting to produce a total break in the the connections to the otherv port.

2. In apparatus for utilizing waste gases in the heating stack, a waste gas conduit stack flue having a port, a boiler flue having a port, said ports of the stack and boiler flues arranged a art from the waste gas conduit port and rom each other and without permanent connection and a reversing valve mounted above. said ports for connecting the waste .gas conduit with. the boiler flue or the stack flue at will, the movement of said valve. to establish connection-with one of. said ports acting to produce a total break in the continuity of the connections to the other port.

3. In apparatus for utilizing waste gases in the. heating of boilers and in combination, a conduit forming the waste gas sup ly, a stack conduit, a boiler conduit, all oi'said conduits arranged apart and without perma nent connections, the axis of the waste gas conduit outlet and the axes of the entrance to the conduits for the stack and the boiler being approximately parallel, and means for connecting said waste gas supply with the boiler or stack at will, the means to establish connection with one of said ports acting to produce a total break in the continuity of the connections to the other port, said means including an element for closing a port while the break continues.

4:. In apparatus of and in combination, a pair of ports and a port adapted to. be connected to either of said pair of ports, said ports having their axes substantially parallel and arranged in the'same horizontal plane, and a reversing valve structure mounted above said ports and shiftable at will, the movement of said valve to establish connection with one port of the pair acting to produce a total break in the continuity of the connections to the other port, said structure including an element for closing such other port while such break continues, saidvalve being water sealed with the water seals arranged out of the path of travel of the Waste gases.

5. In apparatus for utilizing waste gases in the heating of boilers and in combination,

continuity of the character described.

fee-

of boilers and in combina-- movement of saidflue having a port, all of said ports arranged in the same horizontal plane and having 10 ing such other port while such break continues, said element being rendered active and inactive by the movements of the structure.

In testimony whereof I aflix my signature in presence of two witnesses.

LAWRENCE s. SCHMIDT.

Witnesses: I

S. A. MGFARLAND, Hermon G. 8mm. 

